bleed air from cooling system?
02-26-2011, 07:06 PM
#2
**Bleeding the system of air:
Start it up and let it run, radiator cap OFF, and let it warm up till the t-stat opens. I rapidly squeeze the upper and lower radiator hose like 20 times while its warming up to help move any air bubbles through the system and by the t-stat on the engine side. When the t-stat opens you’ll see the level drop as you squeeze it, its sucking the coolant through the system. You will also see the coolant start to flow in the radiator fill neck, once it starts to flow the level should drop down a lot, immediately top it off with coolant/water. Then the flow will stop when the t-stat closes. Wait one more time for the t-stat to open again and start to flow, if it drops down again top it off again. Do it a 3rd time if you want to make sure. I always massage the upper hose during the whole process to keep any air bubbles moving through. Always works like a charm. Just keep checking your temp gauge until the t-stat opens for the first time to make sure it’s not sitting there overheating from a trapped bubble. May take 10-15 minutes for the t-stat to open the first time.
If you do start to get hot while sitting there and the t-stat will not open…..you have an air bubble on the engine side of the t-stat. Shut the engine off and rapidly squeeze the upper and lower radiator hoses again. Then start the engine again and see if the t-stat will open. Sometimes you just have to work those hoses to move the air through. Even after it seems topped off after a couple cycles…check it the next time you have a cold engine…top off if needed.
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Start it up and let it run, radiator cap OFF, and let it warm up till the t-stat opens. I rapidly squeeze the upper and lower radiator hose like 20 times while its warming up to help move any air bubbles through the system and by the t-stat on the engine side. When the t-stat opens you’ll see the level drop as you squeeze it, its sucking the coolant through the system. You will also see the coolant start to flow in the radiator fill neck, once it starts to flow the level should drop down a lot, immediately top it off with coolant/water. Then the flow will stop when the t-stat closes. Wait one more time for the t-stat to open again and start to flow, if it drops down again top it off again. Do it a 3rd time if you want to make sure. I always massage the upper hose during the whole process to keep any air bubbles moving through. Always works like a charm. Just keep checking your temp gauge until the t-stat opens for the first time to make sure it’s not sitting there overheating from a trapped bubble. May take 10-15 minutes for the t-stat to open the first time.
If you do start to get hot while sitting there and the t-stat will not open…..you have an air bubble on the engine side of the t-stat. Shut the engine off and rapidly squeeze the upper and lower radiator hoses again. Then start the engine again and see if the t-stat will open. Sometimes you just have to work those hoses to move the air through. Even after it seems topped off after a couple cycles…check it the next time you have a cold engine…top off if needed.
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02-26-2011, 07:22 PM
#3
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thanks for the write up, will give it a try in the morning....i think i'm good though as it is not running hot, just wanted to make sure it didn't have air trapped in it. I drove around for a while on the highway and in town and the hand stays right under 210, but my fans are set at 185 and they came on and went back off so i'm guessing the gauge not too accurate.
02-27-2011, 01:56 PM
#6
I alway after fill the coolant up, drive it for a while, shut off engine, and loose the bleeder scew for few hours, should let all air out. Keep check coolant level next 3 day.
02-27-2011, 04:05 PM
#7
Starting cold and you just refilled the radiator:
Run at idle with radiator cap off, keeping an eye on the level. Keep adding as it goes down. It will probably go up suddenly at some point, maybe overflow, just ignore. After about 15 minutes, the level will suddenly go way down, so top it up, then coolant will start jetting in a continuous stream from the small hose that connects to the front of the filler neck. This means the thermostat has fully opened. Just top up with coolant, put the cap back on, done.
Run at idle with radiator cap off, keeping an eye on the level. Keep adding as it goes down. It will probably go up suddenly at some point, maybe overflow, just ignore. After about 15 minutes, the level will suddenly go way down, so top it up, then coolant will start jetting in a continuous stream from the small hose that connects to the front of the filler neck. This means the thermostat has fully opened. Just top up with coolant, put the cap back on, done.
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02-28-2011, 02:26 PM
#8
alexus6798,
Just make sure whatever method you choose....periodically check your temp guage or just have someone sit in the car and watch it while your under the hood. Because if there is an air bubble on the engine side of the t-stat thats gonna be stubborn as hell its not going to open and you will sit there and overheat the block and heads.
Just squeeze that upper radiator hose rapidly after the first few minutes of it warming up....that will move the air bubble right by the t-stat....and it will flow coolant as soon as it gets to the t-stats rated temp.
.
Just make sure whatever method you choose....periodically check your temp guage or just have someone sit in the car and watch it while your under the hood. Because if there is an air bubble on the engine side of the t-stat thats gonna be stubborn as hell its not going to open and you will sit there and overheat the block and heads.
Just squeeze that upper radiator hose rapidly after the first few minutes of it warming up....that will move the air bubble right by the t-stat....and it will flow coolant as soon as it gets to the t-stats rated temp.
.
02-03-2018, 01:11 PM
#10
From the dead but. I have a quick scenario. I am using this method.
so far replaced radiator cap replaced water pump with ls2 style water pump along with 160 stat..
at 228 according to hptuners... only steam and a few drops come from the hose under the throttle body from the coolant bypass lines. No flow of fluid is coming from the coolant bypass T under the throttle body.
then steam from the overflow tank. And some from the second port under the radiator cap.
question when I do this will I need to cap off the second port down from the cap that the coolant bypass feeds to on the radiator?
also how will the stat open if I have the cap off outing antifreeze in.
this
so far replaced radiator cap replaced water pump with ls2 style water pump along with 160 stat..
at 228 according to hptuners... only steam and a few drops come from the hose under the throttle body from the coolant bypass lines. No flow of fluid is coming from the coolant bypass T under the throttle body.
then steam from the overflow tank. And some from the second port under the radiator cap.
question when I do this will I need to cap off the second port down from the cap that the coolant bypass feeds to on the radiator?
also how will the stat open if I have the cap off outing antifreeze in.
this
